It is known in the art relating to drive systems for diesel electric locomotives and the like to provide a railway truck mounted axle hung electric traction motor partially supported upon and geared to a drive axle by engaged pinion and drive gears. The gears are lubricated by heavy fluid lubricant contained in a gear case surrounding the gears on the pinion end of the traction motor and on the axle.
To restrict the escape of lubricant from the gear case along the traction motor shaft, the motor is provided with an outer seal. This combines with a shaft mounted oil slinger to direct lubricant escaping past a labyrinth toward internal drain openings in the outer seal through which the lubricant is returned to the gear case. Excess lubricant escapes past a partition plate to an external drain in the pinion end bearing cover and is lost from the gear case.
Under certain operating conditions when the lower part of the drive gear is turning in a direction toward the pinion and the lubricant level in the gear case is relatively high, sufficient lubricant may be pushed or thrown toward the pinion to cause a build-up of lubricant in the vicinity of the internal drain openings. This can force lubricant through the openings into the slinger area and result in a loss of lubricant in the gear case. The effect of this condition, as well as the possibility of excess lubricant flow from the pinion along the traction motor armature shaft and into the slinger area, combine to result in the possibility of excess lubricant loss, requiring inspection and replacement of lubricant at shorter than desired time intervals.